Answer:
As of RFEM 5.27, there has been an adjustment in the solver that should better recognize hinge chains, which can make models unstable in the newer versions.
Adjustments in the solver regarding the consideration of line hinges - hinge chains (two surfaces each with a line hinge for the rotation about x on the same line) now lead to instabilities.
Please check your model accordingly.
- Double line hinges
- Line hinges on free surface edges
